1. Field of the Invention
The present invention relates to an image forming apparatus for forming a superposed image by writing an electrostatic latent image on an image carrier by scanning-type write means, forming a toner image by developing the electrostatic latent image using toner, and transferring the toner image to an intermediate transfer body, and more particularly relates to an image forming apparatus in which, during the running of the intermediate transfer body, when fluctuations occur in the direction orthogonal to the running direction, image distortion and shift are suppressed to prevent the deterioration of image quality.
2. Description of the Related Art
A known conventional image forming apparatus comprises a belt position detection means for detecting belt position in the direction orthogonal to the belt movement direction of an intermediate transfer belt, the belt slippage of the intermediate transfer belt being controlled by controlling the orientation of an adjustment roller in accordance with the belt position detected by belt position detection means (for example, see Japanese Unexamined Patent Application No. 2002-287527 (Prior Art 1).
Another known apparatus is an image forming substance removal device in which, by detection of the slippage of an offset belt by a sensor and the actuation of an actuator based on the result thereof, the position of one end of a tracking roller is changed to alter the position where contact of the offset belt supported by the tracking roller with a driving roller begins and correct the slippage of the offset belt. (For example, see Japanese Unexamined Patent Application No. H8-137351 (Prior Art 2).
However, in the image forming apparatus described in Prior Art 1, a small displacement of the intermediate transfer belt occurs even though the belt slippage is controlled and, accordingly, there is room for improvement in terms of suppressing the image warp and shift produced by this small displacement to prevent deterioration of image quality.
In addition, even thought the technology of the image forming substance removal device described in Prior Art 2 has application in an intermediate transfer belt, similarly to the image forming apparatus described in Japanese Unexamined Patent Application No. 2002-287527 (Prior Art 2) a small displacement of the intermediate transfer belt occurs and, accordingly, there is room for improvement in terms of suppressing the image warp and shift produced by this small displacement to prevent deterioration of image quality.